{"instruction": "You are an expert in named entity recognition. Please extract entities that match the schema definition from the input. Return an empty list if the entity type does not exist. Please respond in the format of a JSON string.", "schema": ["Chemical", "Disease"], "input": "In spontaneously hypertensive , stroke - prone rats , microinjection of methyldopa into the area of the midline B3 serotonin cell group in the ventral medulla caused a potent hypotension of 30 - 40 mm Hg , which was maximal 2 - 3 h after administration and was abolished by the serotonin neurotoxin 5 , 7 - dihydroxytryptamine ( 5 , 7 - DHT ) injected intracerebroventricularly ."}
{"Chemical": ["methyldopa", "serotonin", "5 , 7 - dihydroxytryptamine", "5 , 7 - DHT"], "Disease": ["hypertensive", "stroke", "hypotension"]}